Defensive signals are considered to be an advanced phase of the game and most beginning tournament players don't get much beyond using simple attitude signals. In fact, the expert player has at his disposal the ability to signal for attitude, count, or suit preference. There are also sophisticated coded signals which can show attitude and suit preference at the same time.//
In most cases, it is the responsibility of a good partner to signal properly at the appropriate time. This, of course, leads to different interpretations concerning what is and what is not a "proper signal" at an "appropriate time".
Today's hand provides a good example of expert defense gone astray. The competition was match point duplicate. East-West did well to force the opponents to the three level, and North- South were eager to take the bait and bid on to the heart game. If you look at all four hands it is easy to defeat this contract two tricks. But you can't look at all four hands, and things are not always as they seem.
West decided to start by leading the ace of diamonds. This immediately gives an extra trick to declarer. East should play a card that gives West some idea of how to continue. If East holds the king, a high card, like the nine, would be appropriate. In this instance East does not hold the king and so plays the deuce, which indicates that there are no more tricks available in the diamond suit and a switch is in order.
West has a natural switch to the king of clubs. Many would argue that the king of clubs is the correct opening lead. It certainly makes the defense on this hand easier. At any rate, this card is played to trick two and once again East has to decide how to contribute to the defense. With the actual holding, it is time for East to get busy. West would not be leading the king of clubs from some empty club holding. If West did not hold the queen he would more than likely lead a low club. It must be right to overtake the king with the ace and then continue with the jack and the three back to the queen, defeating the contract.
Another choice would be to signal with the jack. Most players, however, are not going to use an honor card as a signal, and it is not clear how partner will react to that play if it comes up. The last choice, of course, is the three of clubs. When the hand was actually played, that was the card selected by East. When the king held the trick, West was somewhat taken aback and ultimately determined that declarer had the ace of clubs and was holding up for some reason.
It really looked as though East held the king or king-jack of spades and wanted a spade shift. West complied and declarer made five heart tricks, four spade tricks and the king of diamonds for a total of ten, scoring the "impossible" game.
In the post mortem (why is there always a post mortem?), East thought that the two of diamonds was a suit preference card and that there was no further need to signal in clubs. West was sure that the two of diamonds was an attitude signal, as was the three of clubs. The bottom line is that East knew that it was correct to continue with clubs and should have made sure that his partner never had the chance to go wrong. Stay alert for these situations and your partner will heap praise upon you. =================================================================